The Act Of Arc SiRNA Via The Lentivirus On The Memory Consolidation Of The Amygdala-kindled Rats

Objective We are interested in the act of Activity-regulated cytoskeletal proteinsiRNA via the lentivirus on the learning and memory function of theamygdala-kindled rats, and to explore the role of Arc in epilepsy associated withcognitive dysfunction.Method After anesthesia60male Sprague Dawley rats were implanted bothstimulating electrodes in the left amygdala basolateral nucleus (anterior fontanelle-2.8mm,left+4.9mm,subdural-8.6mm) and injection cannula in the right of thedorsal hippocampus (anterior fontanelle-3.6mm,right-2.2mm,subdural-2.5mm).After built the amygdala-kindled model of rats by electrical stimulation of the leftamygdala basolateral nucleus,60rats are divided into three groups randomly: thesilencing lentivirus injecting group(n=20), the null vector lentivirus injectinggroup(n=20) and the0.9%sodium chloride injecting group(n=20). Arc siRNAlentiviral expression vector that was successfully constructed, the null vectorlentivirus and saline were injected into the right side of the dorsal hippocampus ofthe three groups of rats. Two weeks later, we detected the different ability ofmemory retention of rats in each group by the number of shuttled and theincubation period in the passive avoidance test. In order to detect the rats spatiallearning and memory consolidation ability, we observed the rats escape latencyand crossing times and the lag time of platform quadrant in Morris water mazeexperiment. Q-PCR and western-blot are performed to confirm the silenceefficiency of Arc silencing. The experimental data were used completely randomized design variance analysis, using the SPSS17.0statistical package, anddifference was statistically significant when P <0.05.Result The passive avoidance test: The number of shuttled was increasedand the incubation period was decreased in Arc silencing group, comparing to theother two groups, and the difference was statistically significant (P <0.05).Morris water maze experiment: In the first five Navigation test days, the escapelatency of rats was longer in Arc silencing group on the third, four or five daysthan the other two groups, and the difference was statistically significant (P<0.05). With the increasing of the number of experimental days, escape latency ofeach group emerged gradually shorten, but it`s not significant in Arc silencinggroup comparing to the other two groups (P>0.05). In the space search experiment,crossing times and the lag time of platform quadrant were significantly decreasedin Arc silencing group, comparing to the other groups, and the difference wasstatistically significant (P <0.05). And there`s no significant difference of thespatial learning and memory consolidation ability in the other two groups(P>0.05).Q-PCR and western-blot: The expression of Arc mRNA and protein wassignificantly decreased in Arc silencing group, comparing to the other groups, andthe difference was statistically significant (P <0.05). And there is no significantdifference in the other two groups(P>0.05).Conclusion The memory consolidation ability is impaired in the Arcsilencing amygdala-kindled rats and the Arc may play a significant role in theconsolidation of the memory in the amygdala-kindled rats.